Expand WTF::StringView's API to be more like StringPiece.

third_party/WebKit/Source/core/layout/LayoutListMarker.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Andrew Wellington (proton@wiretapped.net)
  * Copyright (C) 2010 Daniel Bates (dbates@intudata.com)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 185 matching lines @@
         m_text = ListMarkerText::text(style()->listStyleType(), m_listItem->value());
         break;
     }
 }
 
 LayoutUnit LayoutListMarker::getWidthOfTextWithSuffix() const
 {
     if (m_text.isEmpty())
         return LayoutUnit();
     const Font& font = style()->font();
-    LayoutUnit itemWidth = LayoutUnit(font.width(m_text));
+    LayoutUnit itemWidth = LayoutUnit(font.width(TextRun(m_text)));
     // TODO(wkorman): Look into constructing a text run for both text and suffix
     // and painting them together.
     UChar suffix[2] = { ListMarkerText::suffix(style()->listStyleType(), m_listItem->value()), ' ' };
     TextRun run = constructTextRun(font, suffix, 2, styleRef(), style()->direction());
     LayoutUnit suffixSpaceWidth = LayoutUnit(font.width(run));
     return itemWidth + suffixSpaceWidth;
 }
 
 void LayoutListMarker::computePreferredLogicalWidths()
 {
@@ skipping 230 matching lines @@
     if (style()) {
         // Reuse the current margins. Otherwise resetting the margins to initial values
         // would trigger unnecessary layout.
         newStyle->setMarginStart(style()->marginStart());
         newStyle->setMarginEnd(style()->marginRight());
     }
     setStyle(newStyle.release());
 }
 
 } // namespace blink